Embodiments of the present invention relate to a battery attachment apparatus to which an electric tool battery is detachably attached.
Nowadays, electric tool batteries are increasingly used as the drive power source of electric tools. When there is little residual capacitance remaining, the electric tool battery is detached from the tool main body, and is attached to a dedicated charger for recharging (See, for example, Japanese Laid-Open Patent Publication No. 2004-147360). A dedicated diagnosis device which is also referred to as a battery checker and which is used to check the electric tool battery for abnormality is known. The diagnosis device diagnoses the number of times that the attached electric tool battery has been recharged, the battery voltage, and the battery inner resistance thereof. Additionally, the diagnosis device diagnoses the battery capacitance, and the electric tool battery as a whole. The diagnosis device formulates the battery condition in the form of diagnosis results and outputs and displays them to the user. The electric tool battery is detachably attached to the charger and the diagnosis device.
Hereinafter, the apparatus other than the tool, to which the electric tool battery is detachably attached, will be generally referred to as a battery attachment apparatus. From the viewpoint of convenience in use, the battery attachment apparatus may desirably be hung on the wall. To obtain a wall-hanging type battery attachment apparatus, the case is provided with a lock hole into which a wall-hanging screw that is mounted to the wall is inserted (See, for example, Japanese Utility Model Publication No. H04-004446). The lock hole is formed so as to establish communication between the exterior and the interior of the case. When the case is molded by using plastic (synthetic resin) as the material, the lock hole is formed along with the other exterior configuration of the case.
Foreign matter may enter the interior of the case from the exterior of the case through the lock hole, because the lock hole is formed so as to establish communication between the exterior and the interior of the case. Consequently, static electricity may also enter the interior of the case from the exterior of the case through the lock hole to adversely affect the interior electronic components. Such a problem is becoming more and more conspicuous because recently, as the battery attachment apparatus has been reduced in size.
Thus, there is a need for a battery attachment apparatus which is configured to prevent a malfunction of the product by preventing intrusion of both foreign matter and static electricity from the exterior into the interior of the case through the wall-hanging lock hole.